Indicia reading terminals for reading decodable indicia are available in multiple varieties. For example, minimally featured indicia reading terminals devoid of a keyboard and display are common in point of sale applications. Indicia reading terminals devoid of a keyboard and display are available in the recognizable gun style form factor having a handle and trigger button (trigger) that can be actuated by an index finger. Indicia reading terminals having keyboards and displays are also available. Keyboard and display equipped indicia reading terminals are commonly used in shipping and warehouse applications, and are available in form factors incorporating a display and keyboard. In a keyboard and display equipped indicia reading terminal, a trigger button for actuating the output of decoded messages is typically provided in such locations as to enable actuation by a thumb of an operator. Indicia reading terminals in a form devoid of a keyboard and display or in a keyboard and display equipped form are commonly used in a variety of data collection applications including point of sale applications, shipping applications, warehousing applications, security check point applications, and patient care applications, and personal use, common where keyboard and display equipped indicia reading terminal is provided by a personal mobile telephone having indicia reading functionality. Some indicia reading terminals are adapted to read bar code symbols including one or more of one dimensional (1D) bar codes, stacked 1D bar codes, and two dimensional (2D) bar codes. Other indicia reading terminals are adapted to read OCR characters while still other indicia reading terminals are equipped to read both bar code symbols and OCR characters.
In imaging based barcode scanning using indicia reading terminals, one method for image acquisition in an embedded system includes using a dedicated camera/video interface integrated into a CPU or microcontroller of the terminal. Another method is to use an image buffer between a camera interface and the CPU or microcontroller. In the latter method, the CPU/microcontroller can read data of an image from the image buffer via, for instance, a parallel memory interface. However, both methods are prohibitive for low-cost scanner solutions because component cost in implementations of these two methods cannot be greatly decreased.